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MicroBooNE detects accelerator-born neutrinos

The MicroBooNE collaboration announced on November 2 that its researchers had recorded neutrinos for the first time. The sighting marks the beginning of detailed studies of these fundamental particles whose properties could be linked to dark matter, matter’s dominance over antimatter in the universe and the evolution of the entire...

Layered Thermal Insulation Systems for Below-Ambient Temperature Applications

With increasing system control and reliability requirements as well as demands for higher energy efficiencies, thermal insulation in extreme environments is a growing challenge prompting the publication of new technical consensus standards for cryogenic insulation testing and multilayer insulation (MLI) systems. Different layered thermal insulation systems such as MLI and...

Cryogenic Safety for Space Launch Vehicles During Ground Operations

United Launch Alliance launches Atlas V from Cape Canaveral and Vandenberg Air Force launch facilities, and large quantities of cryogenic propellants are stored on-site. These propellants present leak, fire and explosion hazards throughout their handling, starting from the commercial transport trailers' arrival at the launch pad and continuing through storage...

Cryogenic Safety: An Introduction

The scope of cryogenics is vast, but in all its forms, cryogenics presents unique safety hazards, including issues associated with extreme cold, flammability, enhanced combustion due to the presence of liquid oxygen and oxygen displacement caused by gases boiling off from cryogenic liquids. Despite these hazards, if certain guidelines and...

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Regenerators

Regenerators or regenerative heat exchangers are a key component of cryocoolers such as pulse tube cryocoolers (Cold Facts, August 2014). Regenerator performance greatly affects the coefficient of performance of cryocoolers. Improvements in regenerator design and, in particular, regenerator materials have been an important factor in the improvement of the performance...

Pulse Tube Cryocoolers

The development of pulse tube cryocoolers has been a significant topic of research and development over the past 20 or so years. Pulse tube cryocoolers have a number of advantages over other types of cryocoolers and are now available commercially. In order to understand pulse tube cryocoolers, it’s best to...

Thermal Expansion

Thermal expansion refers to the change in size (length or volume) that a material undergoes as its temperature changes. In cryogenic systems this effect can be quite large and must be allowed for in the design. In isotropic materials, which include most engineering materials, the thermal expansion is the same...

Magnets

From “Superconductivity: Present and Future Applications” by the Coalition for the Commercial Application of Superconductors. Particle physics uses accelerators to recreate the conditions of the early universe in an attempt to piece together the complex puzzle of how we got to where we are today. These huge machines are used...

Energy Storage

From “Superconductivity: Present and Future Applications” by the Coalition for the Commercial Application of Superconductors. With power lines increasingly congested and prone to instability, strategic injection of brief bursts of real power can play a crucial role in maintaining grid reliability. Small-scale Superconducting Magnetic Energy Storage (SMES) systems, based on...

Astronomy

ASTRONOMY IN SPACE by Peter V. Mason, retired,  Jet Propulsion Laboratory, and Visiting Associate, California Institute of Technology. Pmason@alumni.caltech.edu In thinking about the reasons to perform astronomy in space, we first consider the effect of the earth’s atmosphere.  On a scale of decreasing energy, gamma rays, cosmic rays, X-rays and...

Cryocoolers

What is a Cryocooler? A mechanism that can extract heat from an object (cooler) and by doing so draw its temperature down below approximately 150 Kelvin (cryo). — (Courtesy Dr. Willy Gully) What is the difference between a Cryocooler and a Cryostat? A cryostat is any device designed to maintain...

An Issue of Pressure and Flow Rate in a Supply Tank

Please help solve this problem: A supply tank requires a vaporizer to generate sufficient pressure to pump stored fluid up into a vehicle or tank. The available head is limited as the tank level falls and it is important to minimize the system pressure drop to maintain the desired flow...

Using MLI on VJ Line Joints or Cryo Storage Tanks

When installing Multi Layer Insulation (MLI) blankets on VJ line joints or cryo storage tanks should they be wrapped and tied down tight or loose? These are usually pre-cut to size. Also should they have an access hole at the point of where the molecular sieve is installed to help...